Today's telecommunications equipment sites employ a power management system (PMS) to which three-phase mains power is provided. Conventional PMS evaluates the three phases, converts what it regards as the two best phases into single-phase power and uses the single-phase power to run the equipment (e.g., telecommunications equipment and other loads, such as air conditioning equipment) at the site. If two of the mains phases are lost, the PMS causes the equipment at the site to operate on a backup generator.